thin, flexible barrier around a cell; regulates what enters and leaves the cell. It also provides protection and support. Also called a plasma membrane.
strong supporting layer around the cell membrane in plants, algae, and some bacteria. Main function is to provide support & protection for the cell.
double-layered sheet that forms the core of nearly all cell membranes. There are 2 layers of lipids. It allows the cell membrane to be flexible and forms a strong barrier between teh cell and its surroundings.
the mass of solute in a given volume of solution, or mass/volume
process by which molecules tend to move from an area where they are more concentrated to an area where they are less concentrated
when the concentration of a solute is the same throughout a solution
diffusion of WATER through a selectively permeable membrane
when the concentration of two solutions is the SAME
when comparing two solutions, the solution with the greater concentration of solutes. Remember "hyper" means "high" so, hypertonic is "high solute." So if a solution is hypertonic, it will pull water out of a cell, shrinking the cell.
when comparing two solutions, the solution with the lesser concentration of solutes. Remember "hypo" means "low" so hypotonic is "low solute." So if a solution is hypotonic, it will cause water to be sucked into the cell, swelling and bursting the cell.
movement of specific molecules across cell membranes through protein channels. This is still a type of diffusion, so no cell energy is needed to make it work.
energy-requiring process that moves material across a cell membrane against a concentration difference. Basically, it needs energy to move the material though the membrane.
process by which a cell takes material into the cell by infolding of the cell membrane. A type of active transport.
process in which extensions of cytoplasm surround and engulf large particles and take them into the cell. Means "cell eating." A type of active transport.
process by which a cell takes in liquid from the surrounding environment. A type of active transport.
process by which a cell releases large amounts of material. A type of active transport.